Portable thermal therapeutic apparatus and method

ABSTRACT

A portable thermal therapeutic apparatus, adapted to transfer heat between a creature and the atmosphere by circulating heat transfer fluid within a conduit held in contact with the creature. The apparatus includes a housing with a support structure that is particularly adapted for portable use. A heat pump is disposed within the housing, and operates to transfer heat between a first portion and a manifold. A heat sink is thermally coupled to the first portion, and transfers heat between the first portion and the atmosphere. A pump is disposed within the housing and circulates the fluid through the manifold and the conduit. A power supply is disposed within the housing and drives the pump, thereby causing the fluid to circulate within the manifold and the conduit. The power supply is also provides direct current to the heat pump, thereby causing heat to flow from the manifold to the first portion.

This is a continuation of U.S. patent application Ser. No. 13/012,010,now issued as U.S. Pat. No. 8,449,589, originally filed on Jan. 24,2011, which was a continuation of U.S. patent application Ser. No.10/886,413 now issued as U.S. Pat. No. 7,959,657, originally filed onJul. 7, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to hot and cold therapy apparatus andmethods. More specifically, the present invention relates to portablesolid-state thermal therapeutic apparatus and methods employing heatpump heat transfer devices and a circulating working fluid to cool andwarm body parts.

2. Description of the Related Art

The benefits of hot and cold therapy in treatment of various human andanimal conditions are well documented. Various apparatus have beendevised to achieve the desired transfer of heat between a creature,human or animal, and such an apparatus. Classic examples are the hotwater bottle and the ice pack. Modern medicine now recommends specificamounts of heat transfer for specific durations of time as are indicatedfor various physical ailments and conditions. For example, soft tissueinjuries often indicate cold therapy immediately after injury forseveral hours. Lower back pain can be treated with heat therapy toalleviate pain.

Traditionally, hot and cold therapy has been accomplished with theaffected individual in a fixed position. Such thinking corresponded tothe concept of limited physical movement of the patient during therapyor recovery from injury. However, patients often desire some degree ofmobility during therapy. Movement and mobility during hot and coldtherapy, generally thermal therapy, is acceptable in the case wherethere is no undue strain to the affected portion of the patient's body.In fact, some movement of the affected area is tolerable, and sometimesdesirable. Given the need and desire for mobility during thermaltherapy, some devices and apparatus have been brought to market. Oneexample is the ice chest and bladder cold therapy system. In the icechest system, the user carries and insulated chest that contains amixture of ice and water, along with a pump and battery. A pair of hosesis coupled the chest and pump and to a body-worn bladder, which is heldagainst the affected portion of the patient's body. The patient is ableto carry the chest as they move about. Some significant limitations ofthis approach are the size and bulk of the systems vis-à-vis carryingit, and the lack of control over temperature.

Efforts to reduce the size and weight, and enhance the controllabilityof portable thermal therapy systems have not kept pace with the needsand desires of patients, therapists and doctors. The use of Peltiereffect solid thermoelectric modules (hereinafter “TEM” or “TEM's”) hasbeen considered, as is evident in the prior art. For example, U.S. Pat.No. 5,097,829 to Quisenberry for “Temperature Controlled Cooling System”teaches a TEM heat pump cold therapy device with a temperature controlsystem. A circulating fluid is used with a thermal blanket. A pumpcirculates the fluid, and a fin type heat exchanger removes the wasteheat. A pulse width modulated electrical signal powers the TEM pump tocontrol temperature. However, the Quisenberry device is only for fixedoperation, receiving substantial power input from the utility powergrid.

Another reference is U.S. Pat. No. 5,174,285 to Fontenot for “LocalizedHeat Transfer Device.” Fontenot teaches a TEM pump cooler that employs ahermetically sealed fluid circuit and a peristaltic pump. The closedloop system prevents the working fluid from being contaminated. Areversible cassette can be changed to make it a heat therapy unit.However, the Fontenot device is also only powered from the utility grid,and is of substantial size and power consumption. Another reference isU.S. Pat. No. 5,895,418 to Saringer for “Device for Producing ColdTherapy.” Saringer teaches a TEM cooling device similar to Quisenberry,but adds a thermal reserve in the form of a tank of liquid. The physicalstructure of the heat exchanger is such that the device can be madesomewhat smaller than the prior designs. However, Saringer is still afixed position device, not contemplating the aforementioned desiredmobility aspects. Thus it can be understood, there is a need in the artfor a compact and portable thermal therapy device capable of both hotand cold therapy in such a configuration as to enable comfortableportable operation.

SUMMARY OF THE INVENTION

A portable thermal therapeutic apparatus, adapted to transfer heatbetween a creature and the atmosphere by circulating heat transfer fluidwithin a conduit held in contact with the creature is taught. Theapparatus includes a housing with a support structure that isparticularly adapted for portable use. A heat pump is disposed withinthe housing, and operates to transfer heat between a first portion and amanifold. A heat sink is thermally coupled to the first portion, andtransfers heat between the first portion and the atmosphere. A pump isdisposed within the housing and circulates the fluid through themanifold and the conduit. A power supply is disposed within the housingand drives the pump, thereby causing the fluid to circulate within themanifold and the conduit. The power supply is also provides directcurrent to the heat pump, thereby causing heat to flow from the manifoldto the first portion.

In a specific embodiment of the foregoing invention, a fan is included,which receives power from the power supply. The fan circulates theatmosphere about the heat sinking, thereby be enabling heat transfer byforced convection. In another embodiment, the power supply includes arechargeable battery. An external power source input connector may beadded to the power supply. The external input is used to couple externalpower from the utility power grid or from a power outlet of a vehicularpower supply.

In another specific embodiment, the apparatus includes a fluid reservoirdisposed within the housing that is coupled along the conduit to hold areserve of fluid therein. The housing may be insulated against the flowof heat. The housing may be padded on its exterior surfaces. In arefinement to the invention, the apparatus further includes a displayand an actuator. A controller in the housing operates to interpretactuation of the actuator as input of a temperature set point. Thecontroller then displays the temperature set point on the display. Inother specific embodiments, the support structure is a shoulder strap ora belt. In a particular embodiment, the housing and the supportstructure are configured as a backpack.

In order to minimize the size and weight of the apparatus, apiezoelectric pump is employed in one embodiment. In another embodiment,the apparatus further includes a temperature sensor positioned to sensethe temperature of the fluid as it exits the manifold. The temperaturesensor has a temperature signal output, and the power supply operates toadjust the direct current flow to the heat pump in response to thetemperature signal. In another embodiment, the power supply operates toreverse the polarity of the direct current, thereby reversing the heatflow through the heat pump, causing heat to flow from the first portionto the manifold.

In a particular embodiment, the housing is divided into a first housingportion attached to a first location along the support structure and asecond housing portion attached to a second location along the supportstructure. The pump, the heat pump, and the heat sink are located withinthe first housing portion, and the power supply is located in the secondhousing portion. This embodiment allows the weight and bulk of theapparatus to be distributed about a user's body.

In another specific embodiment, the apparatus of Claim 1, furtherincludes a temperature sensor positioned to sense the temperature of thefluid as it exits the manifold. The temperature sensor outputs atemperature signal. A controller receives the temperature signal. Thecontroller causes the power supply to adjust the direct current flow tocause the temperature signal to reach a predetermined set-pointtemperature. In another refinement of the invention, the controlleradjusts the direct current flow to cause the temperature signal to reacha plurality of predetermined set-point temperatures over a plurality oftime intervals. A communications port is coupled to the controller inanother embodiment. The controller is remotely programmable through thecommunications port.

In an illustrative embodiment of the present invention, a portablethermal therapeutic apparatus, adapted to transfer heat between acreature and the atmosphere by circulating heat transfer fluid within aconduit held in contact with the creature is taught. The apparatusincludes a housing with a padded exterior covering that is insulatedagainst the flow of heat, and has a support structure adapted forportable use. Plural Peltier effect heat pumps, having a combinedcooling capacity of approximately twenty watts at a differentialtemperature of approximately thirty-five degrees Celsius, are disposedwithin the housing. They operate to transfer heat between a firstportion and a manifold. A heat sink is thermally coupled to the firstportion, and transfers heat between the first portion and theatmosphere. A fan is positioned to circulate the atmosphere about theheat sink, thereby enabling heat transfer by forced convection. Apiezoelectric pump that has a flow capacity greater than one-halfliter-per-minute at five pounds per square inch pressure is disposedwithin the housing. The pump circulates the fluid through the manifoldand the conduit. A fluid reservoir is also disposed within the housing,and is coupled between the piezoelectric pump and the conduit. A powersupply, with a lithium-ion rechargeable battery of approximatelyone-hundred eighty watt-hour capacity and an external power source inputconnector for coupling external power from the utility power grid orfrom a power outlet of a vehicular power supply is disposed within thehousing. The power supply drives the pump, thereby causing the fluid tocirculate within the manifold and the conduit. The power supply alsodrives the fan and further provides the direct current to the heat pump,thereby causing heat to flow from the manifold to the first portion. Atemperature sensor is positioned to sense the temperature of the fluidas it exits the manifold. A temperature signal is output from thesensor. A display and an actuator are disposed on an exterior surface ofthe housing. A controller is coupled to the temperature sensor, thedisplay, the actuator, and the power supply. In operation, thecontroller interprets actuations of the actuator as a plural temperatureset points and plural time interval inputs. The controller displays thetemperature set points and time intervals on the display. The controllerreceives the temperature signal and adjusts the direct current flow tocause the temperature signal to reach the plurality of predetermined setpoint temperatures over the plurality of time intervals. The controlleralso causes the power supply to reverse the polarity of the directcurrent, thereby reversing the heat flow through the heat pump, causingheat to flow from the first portion to the manifold. A communicationsport is coupled to the controller so that the controller is remotelyprogrammable to receive the plurality of predetermined set-pointtemperatures and the plurality of time intervals.

The present invention also teaches a method of applying thermal therapyusing a portable apparatus enclosed in a housing with a supportstructure. The method includes the steps of supporting the housing fromthe user's body by engaging the support structure to the user's body,and placing a conduit having heat transfer fluid therein into contactwith the body of a user, thereby transferring heat between the user andthe heat transfer fluid. Also, the steps of coupling the conduit to apump and a manifold of a heat pump disposed within the housing, andapplying power to the pump, by a power supply disposed within thehousing, thereby circulating the heat transfer fluid through the conduitand the manifold. Finally, delivering direct current to the heat pump,by the power supply, thereby transferring heat between the heat transferfluid in the manifold and the heat sink.

In a refinement to the foregoing method, and additional step of blowingthe atmosphere against the heat sink using a fan disposed within thehousing, thereby transferring heat by forced convection is added. Inanother refinement, the method includes the additional step ofdelivering electric current to the power supply from a rechargeablebattery. A further refinement of the method includes the additional stepof recharging the battery from the utility power grid or operating theapparatus from a power outlet of a vehicular power supply. Anotherembodiment adds the step of circulating the heat transfer fluid througha fluid reservoir disposed within the housing. To improve thermalefficiency, the step of insulating the housing against the flow of heatis added.

In a specific embodiment of the foregoing method, the method includesthe additional steps of entering a set-point operating temperature usingan actuator disposed on the housing, and displaying the set-pointtemperature on a display disposed on the housing. In another embodiment,the steps of sensing the temperature of the heat transfer fluid as itexits the manifold, and adjusting the direct current flow to the heatpump in response to the sensed temperature are added. In anotherrefinement, the step of reversing the polarity of the direct current, bythe power supply, thereby reversing the heat flow through the heat pumpis added.

In another specific embodiment of the method, the method includes thefurther steps of sensing the temperature of the heat transfer fluid asit exits the manifold, and adjusting the flow of direct current to theheat pump, thereby causing the temperature to reach a predeterminedset-point. In another improvement, the further step of adjusting theflow of direct current, thereby causing the temperature to reach aplurality of predetermined set-point temperatures over a plurality oftime intervals is added. In another specific embodiment of the method,the method includes the further steps of sensing the temperature of theheat transfer fluid as it exits the manifold, and adjusting the flowrate of the pump, thereby causing the temperature to reach apredetermined set-point.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing of a shoulder-worn thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 2 is a drawing of a belt-worn thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 3 is a drawing of a backpack-worn thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 4 is a drawing of a computer programming station for a thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention.

FIG. 5 is a top view drawing of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 6 is an end view drawing of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 7 is an end view drawing of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 8 is a side view drawing of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 9 is a heat flow diagram of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 10 is a functional block diagram of a thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 11 is a top view of the internal components in a thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention.

FIG. 12 is a partial end view illustrating the user interface of athermal therapeutic apparatus according to an illustrative embodiment ofthe present invention.

FIG. 13 is a side section view of the internal components in a thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention.

FIG. 14 is an end view of the internal components in a thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention.

FIG. 15 is an operational flow diagram of a method of operating athermal therapeutic apparatus according to an illustrative embodiment ofthe present invention.

FIG. 16 is a drawing of a belt-worn thermal therapeutic apparatusaccording to an illustrative embodiment of the present invention.

FIG. 17 is a functional block diagram of a two enclosure thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention.

DESCRIPTION OF THE INVENTION

Illustrative embodiments and exemplary applications will now bedescribed with reference to the accompanying drawings to disclose theadvantageous teachings of the present invention.

While the present invention is described herein with reference toillustrative embodiments for particular applications, it should beunderstood that the invention is not limited thereto. Those havingordinary skill in the art and access to the teachings provided hereinwill recognize additional modifications, applications, and embodimentswithin the scope hereof and additional fields in which the presentinvention would be of significant utility.

The illustrative embodiments of the invention teach a portable bodycooling and warming apparatus that enables users to access cold and heattherapy at fixed locations as well as when mobile, such as riding is acar, walking, and during other physical activities. A rechargeablebattery power source and charger are provided in a body-wornthermoelectric cooling and heating apparatus so that users can drawpower from conventional AC sources when available or the battery sourcewhile mobile. The apparatus can be belt-worn, worn using anover-the-shoulder strap, or worn using a backpack style carrier, or wornin a hip-supported configuration. Other portable carrying systems can bereadily implemented as well. Flexible tubing couples the device to athermal body wrap that is attached to the affected portion of the user'sbody.

Heat transfer is accomplished using a Peltier-effect thermoelectric heatpump. The thermoelectric (“TEM”) heat pump is powered by direct current,which forces heat to flow from a cold side to a hot side of the TEM. Ina cooling mode of operation, the cold side of the TEM is conductivitycoupled to a fluid heat exchanger, which has a working fluid circulatingtherein. Heat is drawn from the working fluid as it circulates throughthe heat exchanger. A piezoelectric pump is used to force the workingfluid to flow through the heat exchanger. Flexible tubing couples theworking fluid from the pump and heat exchanger to a flexible body wrap.The body wrap includes fluid channels that direct the working fluidthrough a tortuous path, which is held in close proximity to an affectedarea of the user's body. Heat flows from the user's body to the workingfluid by virtue of the body wrap's placement against the user's body.Thus, heat is removed from the user's body, flows away in the workingfluid, and is removed by action of the TEM heat pump. In a heating modeof operation, the direct current flow to the TEM heat pump is reversed,which causes the flow of heat across the device to be reversed. In thismode of operation, heat is absorbed from the atmosphere by the heatsink, and is transferred to the user's body through the working fluid.

The body wrap can be any of a variety of types known to those skilled inthe art. A pair of flexible conduits couple the body wrap to theapparatus of the present invention. The body wrap may be of the typeemploying a tortuous flow path or may be of the bladder type. Othertypes of body wraps known to those skilled in the art can be employed aswell. The only requirement is that the body wrap accepts a flowingworking fluid medium as the heat transfer mechanism. The flexibleconduit may be conventional tubing, made from any suitable rubber orthermoplastic material.

Reference is directed to FIG. 1, which is a drawing of a shoulder-wornthermal therapeutic apparatus 4 according to an illustrative embodimentof the present invention. The illustration depicts a user 2 who isutilizing thermal therapy to the shoulder area using a body-wornshoulder pad 10. The pad 10 is coupled to the thermal therapeuticapparatus via two flexible hose type conduits 8. The apparatus 4 isslung from the opposite shoulder using a shoulder strap 6 supportstructure. A key to the successful utilization of the present inventionis the compact size and light weight of the apparatus, as well as theportable power management, which enables the user to engage in an activelife-style while still obtaining the needed thermal therapy.

Reference is directed to FIG. 2, which is a drawing of a belt-wornthermal therapeutic apparatus 14 according to an illustrative embodimentof the present invention. The user 12 is applying thermal therapy to anelbow joint using an elbow pad 20 thermal therapy pad. The pad 20 iscoupled to the thermal therapy apparatus 14 using a pair of hoses 18.The thermal therapy apparatus 14 is supported by a belt type supportstructure 16. It should be noted that a given thermal therapy apparatuscan be adapted to engage a variety of support structure types. Thisenables the user and caregiver to select a support system that isconsistent with the needs and comfort of the user in any givenapplication.

Reference is directed to FIG. 3, which is a drawing of a backpack-wornthermal therapeutic apparatus 24 according to an illustrative embodimentof the present invention. The user 22 is applying thermal therapy to aknee joint using a knee-type thermal therapy pad 32. A pair of flexiblehose conduits 30 couple the knee pad 32 to the thermal therapy apparatus24. A pair of should straps 26 and a waist belt 28 provide the necessarysupport structure to form the backpack style system. In many of thesupport structure embodiments, the apparatus and support structureelements are padded to provide comfort to the user. Canvas and syntheticmaterials are suitable for this purpose. The conduit hoses are insulatedagainst the flow of heat so as to maintain the thermal efficiency of thesystem. The exterior of the body-worn pad is also insulated against theflow of heat.

Reference is directed to FIG. 4, which is a drawing of a computerprogramming station for a thermal therapeutic apparatus 34 according toan illustrative embodiment of the present invention. As notedhereinbefore, modern thermal therapy utilizes various temperatures andtime internals for therapy. The present invention is adapted to deliverprogrammable set point temperatures for both heat therapy and coldtherapy. In fact, a mixture of heat and cold therapy can be delivered inone therapeutic session. The present invention simplifies theprogramming operation, where various set-point temperatures and timeintervals are entered into the apparatus 34, by providing a serialinterface to a personal computing device. A serial cable 38 couples theapparatus 34 to a serial port on a personal computing device 36.Application software provided to the user with the apparatus 34 isloaded and executed on the computing device 36. A computer monitor 40and a keyboard 42 facilitate the entry and display of specifiedtemperature set points and time intervals.

Reference is directed to FIG. 5, FIG. 6, FIG. 7, and FIG. 8, which are atop view, coolant connector end view, side view, and user interface endview drawing of a thermal therapeutic apparatus according to anillustrative embodiment of the present invention. The apparatus ishoused in a rigid housing 50 that is formed as a rectangular box-likestructure. Other geometric configurations could be readily employed, andthe corners and edges could be rounded to facilitate comfortablecarrying by a user. A battery 52 is coupled to the bottom of the housing50. Four latches 54 are employed to hold the battery in place. Anysuitable connecting system could be used. In an alternative embodiment,the battery is inserted into the interior of the housing 50. Theexternal battery is advantageous because it allows differing sizes ofbatteries to be used, depending on the amount of battery capacity neededfor a particular application. Each battery 52 includes a DC powerconnector 82, which is coupled to a power supply (not shown) inside ofthe housing 50 by a power cable 80.

Since the apparatus transfers heat between the user and the atmosphere,there are relatively large vents with grills 76, 78 on the working fluidconnector end and user interface end, respectively. The vents enable thefree flow of atmospheric air through the apparatus. The coolantconnector end of the housing 50 presents an inlet coolant connector 56and an outlet coolant connector 58. In the illustrative embodiment,“o”-ring sealed quick connectors with automatic shut-off valve adaptersare employed. This approach allows the user to easily connect theworking fluid conduits that couple to the body-worn pad without leakingsignificant amounts of working fluid. In other embodiments, the workingfluid conduits may be permanently attached, utilizing a closed system.In the illustrative embodiment, a coolant reservoir (not shown) isprovided on the interior of the housing 50. The reservoir provides areserve of working fluid and allows a small amount of air to accumulatein the fluid conduit system without adversely affecting systemperformance. A fill spout and cap 60 are present on the top of thehousing 50. The fill cap 60 is removed to re-fill the coolant conduitsystem when needed.

The user interface of the apparatus is presented on the user interfaceend of the housing 50. In the illustrative embodiment, a digital display62 is provided, which is used to display the present set-pointtemperature and elapsed time, as well as the programming set-pointtemperatures and time intervals during the programming of the apparatus.Touch key actuators 64, 66 are provided to increase and decrease thedesired set-point temperature or the desired time interval duringprogramming or during routine operation. A mode key actuator 68 isprovided to select between different modes of operation, such asoperation, programming, and diagnostic modes of operation. An on and offswitch actuator 70 is provided for the customary purpose. A serial port74 is provided for coupling to an external personal computing device toenable automated programming of the set point temperatures and timeintervals, as well as other configuration parameters of the apparatus.In the illustrative embodiment, as USB serial port is contemplated,however any suitable computer interface known to those skilled in theart could be employed to achieve the needed interface to a computingdevice.

An external power connector 72 is provided for connection of an externalpower source. In the illustrative embodiment, an AC power transformerplugged into a wall outlet coupled to the utility power grid is onesource of external power. Another source of external power is a couplingto the vehicular power adapter, or cigarette lighter socket on a motorvehicle. Those skilled in the art will appreciate that other powersources could be connected to the external power connector 72, providedthat the correct voltage and current requirements for the system weremet. In the illustrative embodiment, a nominal twelve-volt directcurrent source is used. However, the power supply (not shown) could beadapted to convert AC to DC power within the housing 50, so that ACexternal sources could then be coupled to the apparatus.

Reference is directed to FIG. 9, which is a heat flow diagram of athermal therapeutic apparatus according to an illustrative embodiment ofthe present invention. As noted hereinbefore, an important advantage ofthe present invention is its ability to deliver a compact, powerful,man-portable device that provides sufficient run time to allow users toengage in reasonably active life styles while using the system. Theillustrative embodiment provides at least twenty watts of cooling powerfor an estimated run time of three to four hours when the batteries arefully charged, at a differential temperature of thirty-five degreesCelsius. FIG. 9 graphically depicts this capacity in a heat flowdiagram. The system includes the body pad 10, which is coupled byconduits 98 and 104 to the apparatus. The pump 106, cold plate manifold90, TEM module 92, heat sink 94 and fan 96 are illustrated. Inoperation, working fluid is circulated within the conduits at a flowrate equal to or greater than one-half liters per minute through apressure drop of five pounds per square inch. The fluid is cooled in thecold plate 90 and exits at a set-point temperature of one to two degreesCelsius, for example. The fluid is forced through the body pad 100,where heat is absorbed from the body at a rate of twenty watts,continuously. The fluid experiences a temperature gain of approximatelyone degree Celsius as it passes through the body pad 100. Thus, thefluid is returned to the cold plate 90 at that temperature.

The cold plate 92 removes heat from the fluid at a rate slightly greaterthan twenty watts, so the fluid is reduced back to two degrees Celsiusto for further circulation. The heat is removed from the cold plate 92by the Peltier effect of the TEM module 92. Since the ambienttemperature is a nominal twenty-five degrees Celsius, and since the heatsink differential with respect to ambient is about ten degrees Celsius,by virtue of the forced convection induced by the fan, the differentialtemperature of the TEM module is about thirty-five degrees Celsius. Inthe illustrative embodiment, four twenty-nine watt (maximum coolingcapacity) TEM modules are employed that have maximum current and voltageparameters of three amps and seventeen volts, respectively. The powersource is a nominal twelve volt system, with a power supply adjustingcurrent flow to meet the predetermined set-point temperaturerequirement. When working across a differential temperature ofthirty-five degrees Celsius, these modules' combine heat transfercapacity is twenty-eight watts. Thus, a performance margin is realizedfor the twenty-watt design goal. In one embodiment, AdvancedThermoelectric (Nashua, N.H.) model No. ST-127-1.0-3.0 TEM modules arecontemplated. Other manufacturers provide similar modules, which may beconsidered by those skilled in the art. In FIG. 9, the ambient air 95 isheated as it passes through the heat sink 94, and is exhausted togetherwith the waste heat 110.

Reference is directed to FIG. 10, which is a functional block diagram ofa thermal therapeutic apparatus according to an illustrative embodimentof the present invention. This diagram illustrates the variousfunctional component used in the illustrative embodiment. The body-wornpad 114 has the conduit 112 arranged in a tortuous path inside. Couplingconduits 116 connect to fluid connectors 115, 117. In the illustrativeembodiment, a blend of water and ethylene glycol are used as the workingfluid. Other fluids, including pure water may be use. Those skilled inthe art are familiar with suitable heat transfer working fluids andtheir properties. The remaining components comprise the apparatus, mostof which are enclosed in a single housing (not shown), that may befabricated from plastic, aluminum, or other suitable light-weightmaterials, as are known to those skilled in the art. The fluid circuitof the apparatus includes several pieces of connecting conduit 119 thatcouple together the fluid reservoir 118, the pump, and the cold platemanifold 125, which is thermally coupled to the TEM module 126. Thefluid circuit is insulated against the flow of heat by insulation 121. Aplastic cellular-type insulation 121 is employed in the illustrativeembodiment, although any suitable insulation know to those skilled inthe art may be employed. The insulation may also form the paddedenclosure in one embodiment. The fill cap 120 of the fluid reservoir 118extends through the insulation 121 so that the user can replenish thefluid when needed.

The pump 122 in the illustrative embodiment is a piezoelectric pump,which is selected for its compact size, lightweight, and powerefficiency. The pump was developed by Deak Technologies (Hudson, Mass.),and is identified as a DTI-500 series pump. The power supply driving thepump is a twelve-volt nominal oscillating wave, which drives thepiezoelectric crystal to in duce movement the fluid. The flow rate ofthe pump is controlled by the frequency and amplitude of the oscillatingwave. The power supply 140 is adapted to provide the requisiteoscillating wave under control of controller 138. The cold platemanifold 125 is fabricated from aluminum with channels formed therein toform the manifold cavities. The cold plate manifold 125 is thermallybonded to the TEM modules 126 using thermal greases, as are known tothose skilled in the art. The opposite side of the TEM module 126 isthermally bonded to a pair of finned heat sinks 128. The heat sinks 128are thermally coupled to the ambient atmosphere by forced convectioninduced by boxer fan 132. Those skilled in the art are familiar withheat sink design and heat transfer concepts. Ambient air 134 is forcedby fan 132 through the heat sink fins 128, and is exhausted togetherwith the waste heat 130.

The electrical components of the apparatus may be located outside of theinsulation 121, but still within the apparatus housing. This arrangementis advantageous since some heat is produced by the electroniccomponents. The power supply 140 is a solid-state type, which providesdirect current to the TEM modules 126. The current flow to the TEMmodules is adjusted by the controller 138, so that the outputtemperatures of the cold plate 125 can be driven to the predeterminedset point temperatures. The temperature of the working fluid is sensedby temperature sensor 137. The temperature sensor may be a thermaljunction type, a thermistor, or other type of sensor device, as areknown to those skilled in the art. The controller 138 controls the powersupply to drive the fan 132 and the pump 122 during operation of theapparatus. A liquid crystal display 136 and key-matrix keypad ofactuators are also coupled to the controller, and are used in theaforementioned user interface functions. A USB compliant serial port 144is coupled to the controller, and is used to communicate with anexternal personal computing device for programming and controlapplications.

The battery 146 in the illustrative embodiment is a twelve-volt nominallithium-ion rechargeable battery. The capacity is approximately onehundred eighty watt-hours, which yields a typical run time of threehours in cooling mode, longer in heating mode. In the illustrativeembodiment, an Ultralife Batteries, Inc. (Newark, N.Y.) model UBI-2590battery is used. The battery is latched to the exterior surface of thehousing. An external charging contact 148 is provided for couplingutility grid power or DC power form a vehicular connector.

Reference is directed to FIG. 11, FIG. 12, FIG. 13, and FIG. 14, whichare a top section view, a user interface detail, am side sectional viewand an end sectional view of the internal components in a thermaltherapeutic apparatus according to an illustrative embodiment of thepresent invention. The four TEM modules 178 are located near the centerof the housing 150, and are thermally bonded to the cold plate manifold180 and the twin finned heat sinks 182. A boxer fan 184 is positioned atone end of the heat sinks 182, and forces atmospheric air 186 throughthe fins of the heat sinks 182. Heat is transferred to or from the air,which exits 188 the opposite end of the housing 150. Vents are formedinto both ends of the housing 152, and are protected by grills 200. Thecold plate manifold 180 is couple to the working fluid conduits. Thepump 164 draws fluid from the fluid reservoir 160 through conduit 166.The pump discharges the fluid into conduit 172, which feeds the inletend of the cold plate 180. The fluid circulates within the cold platemanifold 180, and exits through conduit 170. Conduit 170 is coupled tofluid outlet connector 158. Fluid inlet connector 156 couples the fluidto the fluid reservoir 160. Connecting the body worn pad (not shown) tothe fluid connectors 156, 158 completes the fluid conduit circuit. Afill cap 162 of the fluid reservoir is presented on the top surface ofthe housing 150, for filling the fluid conduit circuit.

The controller, power supply, and other electrical circuitry are locatedin area 174. The user interface circuitry is located in area 176. Abattery cable 204 couples the electrical circuitry 174 with the battery152 through battery connector 206. The user interface consists of thedisplay 190, the up and down selector actuators 192, 194, the modeswitch actuator 196, the power switch 198, and external power connector204, and the serial port interface connector 202. The functions of thesecomponents were described hereinbefore. Note that the packaging of theapparatus is tight and efficient, enabling a system that is compact andportable, as well as light weigh for convenient user portability.

Reference is directed to FIG. 15, which is an operational flow diagramof a method of operating a thermal therapeutic apparatus according to anillustrative embodiment of the present invention. The method depicted inFIG. 15 is that of a multiple temperature set point and time intervaltherapeutic session. The process begins at step 210 and proceeds to step212. At step 212, the plural temperature set points and time intervalsare stored into a memory of the controller. This data can be inputthrough the user interface with key actuations, or it can be transferredthrough the serial port interface from a personal computing device. Atstep 214, the process checks for user initialization of a therapeuticsession. This is accomplished using the mode key actuator in theillustrative embodiment. If the user has initialized a session flowproceeds to step 216.

At step 216, the controller recalls a present temperature set point andtime interval. The times and temperatures are stored in a memory queue,and are recalled in sequence, with the top data set referred to as the“present” temperature and time. At step 218, the controller sets the TEMcurrent and polarity, using the highest current setting so that thetarget set-point temperature can be reached as quickly as possible. Atstep 220, the controller reads the temperature sensors, which indicatesthe actual fluid temperature. If the set-point temperature has not yetbeen met, flow proceeds to step 222. At step 222, the controller checksthat battery condition. If the battery condition is not low, flowreturns to step 220, where the temperature check is repeated. If thebattery condition is low at step 222, then flow proceeds to step 226. Atstep 226, the controller displays the low battery condition to the userand reduces the TEM current to zero, stopping both the pump and the fanas well. At step 230, at test is made to see if the user has attached anexternal power supply in response to the alert indication. If the userhas not yet attached external power, flow returns to step 226 to renewthe alert. If the user has attached power, then flow returns to step220, to again determine in the target set point temperature has beenreached.

Again considering step 220, if the controller determines that thepresent set-point temperature has been reached, then flow continues tostep 224. At step 224, the controller reduces the run current frommaximum current, since the target temperature has new been reached, andstarts the present interval timer. Note that the timer is not starteduntil the target set-point temperature is reached. This insures that thepatient receives a full measure of treatment. At step 228, thecontroller rechecks the measured temperature. If the temperature hasdrifted from the set point, then the current is adjusted correspondinglyat step 232. On the other hand, at step 228, if the temperature has notdrifted, then flow proceeds to step 234. At step 234, the process checksto see if the present timer has expired. If not, then flow returns tostep 228 to recheck the temperature. If the timer has expired at step234, then the process checks to see if there is another temperature andtime data pair in the memory queue at step 236. If there is, that datais recalled at step 216, where the new temperature and time are actedupon as just described. On the other hand, at step 236, if the there areno more temperature and time data remaining, then the process shuts ofthe apparatus at step 238 and exits the process at step 240.

Reference is directed to FIG. 16, which is a drawing of a belt-wornthermal therapeutic apparatus according to an illustrative embodiment ofthe present invention. The apparatus in FIG. 16 separates the functionalcomponents of the apparatus into two groups so that they can bepositioned along difference portions of the support structure. Thisapproach advantageously distributes both the bulk and weight of theapparatus for more comfortable wear and use. In particular, the user 242wears a belt 250, which has a first portion 246 and a second portion 248of the apparatus distributed there about. The fluid components arelocated in the first portion 246. A pair of flexible hose conduits 252coupled the working fluid between the first portion 246 and thebody-worn pad 254, which is a knee pad in the illustrative embodiment.

FIG. 17 is a functional block diagram of a two enclosure thermaltherapeutic apparatus according to the illustrative embodiment of thepresent invention illustrated in FIG. 41. In FIG. 42, the first portion,or enclosure, 246 houses the fluid reservoir 258, the pump 262, the TEM266, with cold plate manifold 264 and heat sink 270, and the fan 268.The fluid conduit circuit is insulated 256 against the flow of heat. Thebody worn pad 254 is coupled to the second portion 246 with a pair ofconduit hoses 252. The second portion enclosure 248 is coupled to thefirst portion enclosure 248 by a bundled 286 of electrical conductorsthat couples power and control circuits between the two portions. Thesecond portion 248 houses the controller 274, the power supply 276, thebattery 282, the display 272, the keypad 278, the serial port 280, andthe external power connector 284. The functions of the variouscomponents is essentially the same as described regarding thecorresponding components in FIG. 10, and will not be repeated here.

Thus, the present invention has been described herein with reference toa particular embodiment for a particular application. Those havingordinary skill in the art and access to the present teachings willrecognize additional modifications, applications and embodiments withinthe scope thereof.

It is therefore intended by the appended claims to cover any and allsuch applications, modifications and embodiments within the scope of thepresent invention.

What is claimed is:
 1. A portable thermal therapeutic apparatus, fortransferring heat with a creature using a heat transfer fluidcirculating within a conduit held in contact with the creature, andadapted to receive power from a battery; the apparatus comprising: ahousing adapted for portable use of the apparatus; a thermoelectric heatpump, disposed within said housing, operable to transfer heat at a rateproportional to the amount of electric current driving saidthermoelectric heat pump, between an atmospheric heat sink and amanifold having fluid channels formed therein; a fluid pump coupled tocirculate the heat transfer fluid through said manifold and the conduit;a power supply having a battery connector for receiving electric currentfrom the battery, and an external power source input connector forcoupling external power from the utility power grid or from a poweroutlet of a vehicular power supply for recharging the battery; a controlcircuit coupled to said power supply and coupled to provide electriccurrent to drive said thermoelectric heat pump and said fluid pump, andhaving a temperature sensor positioned near a fluid channel of saidmanifold, said control circuit operable to adjustably control the rateat which electric current drives said thermoelectric heat pump inresponse to said temperature sensor, thereby enabling the apparatus toachieve a predetermined set-point temperature of the heat transferfluid, and further enabling the apparatus to maintain said predeterminedset-point temperature over time; a fan aligned to circulate theatmosphere about said atmospheric heat sink, and wherein said controlcircuit is further operable to couple electric current from said powersupply to said fan; an actuator, and wherein said control circuit iscoupled to interpret an actuation of said actuator as a selection of thepredetermined set-point temperature, and wherein said control circuit isoperable to regulate electric current flow to said thermoelectric heatpump until said predetermined set-point temperature has been achieved.2. The apparatus of claim 1 wherein said housing comprises an insulatedportion.
 3. The apparatus of claim 2, wherein a portion of said powersupply and said control circuits are located outside of said insulatedportion of said housing.
 4. The apparatus of claim 1, furthercomprising: a support structure coupled to said housing, and whereinsaid support structure comprises at least one of a shoulder strap wornto engage a shoulder of the creature and a belt worn to engage a waistof the creature.
 5. The apparatus of claim 1 wherein said controlcircuit is operable to reverse the polarity of said power supply,thereby reversing the heat flow through said heat pump.
 6. The apparatusof claim 1 wherein said housing is divided into a first housing portionattached to a first location along said support structure and a secondhousing portion attached to a second location along said supportstructure, and wherein said pump and said thermoelectric heat pump arelocated within said first housing portion, and said power supply islocated in said second housing portion.
 7. The apparatus of claim 1,wherein said thermoelectric heat pump comprises plural thermoelectricheat pumps.
 8. The apparatus of claim 1, further comprising a fluidreservoir disposed within said housing, and coupled between saidmanifold and said fluid pump.
 9. The apparatus of claim 1, and whereinthe battery may be selected from amongst differing sized batteriesdepending on the capacity needed, and wherein: said housing furtherincludes a means for detachably supporting the battery.
 10. Theapparatus of claim 9, and wherein: said means for detachably supportingthe battery is arranged such that a portion of the battery is exposedabout the exterior of said housing.
 11. The apparatus of claim 1, andwherein said control circuit is operable to control the flow rate ofsaid fluid pump in response to said temperature sensor, thereby furthercontrolling power consumption from said power supply.